Probiotic lactic-acid bacteria, which at present are often artificially added to yogurt foods, can have a number of positive effects on health if they are alive when they enter the digestive tract and can attach themselves therein for the longest possible time. Their action is to inhibit colonization by other microorganisms, some of which are deleterious to health, and to establish a desirable, positive intestinal flora. Hence the effectiveness of the probiotic cultures is increased when they are transported into the intestine as efficiently as possible and achieve the highest possible rate of attachment to its walls.